The variability of individual responses to drugs can complicate the treatment of many disorders. Even within a population that is relatively homogenous (i.e., same sex, a narrow range of ages, etc.), some subjects will respond well to a particular drug, while other subjects will respond poorly.
The problem of interpatient variability is particularly serious among sufferers of chronic diseases. For example, many drugs utilized to treat chronic psychological disorders (e.g., depression) require many days or even weeks before an effect, if any, is seen. For subjects that do not respond to the drug, the "wait and see" period only prolongs the period of suffering.
U.S. Pat. No. 5,209,920 discloses a method for predicting susceptibility to inflammatory diseases. The method disclosed involves administering a test compound which is known to affect the hypothalamic-pituitary-adrenal axis, then measuring the levels of pituitary and adrenal hormones. Individuals that do not respond to the test compound with increased pituitary and adrenal hormones are deemed "susceptible." This disclosure does not provide any teaching regarding a method for predicting whether a subject will respond to a particular drug or treatment regimen.
Accordingly, there is a need in the art for a method of predicting the responsiveness of a subject to a particular drug or treatment regimen. A method for predicting responsiveness would allow physicians and other medical professionals to quickly determine an effective drug or treatment regimen for a particular subject, thus reducing the subject's suffering and expense. A method for predicting responsiveness would also reduce or eliminate a subject's exposure to drugs or treatment regimens that are not effective, thereby reducing or eliminating suffering from side effects of such ineffective drugs or treatment regimens.